This invention relates to a wavelength multiplexing optical recording apparatus using an optical recording medium made of a plurality of laminated optical recording layers having wavelength sensitivities, and particularly to a wavelength multiplexing optical recording apparatus suitable for accurately positioning a plurality of laser beams of different wavelengths.
Wavelength multiplexing recording is being proposed as an approach to a drastically enhanced recording density of the optical disk memory. As a recording medium for wavelength multiplexing recording, there is known organic dye molecule monolayers laminated by the Langmuir-Blodget method as described in Nikkei New Material, May 19, 1986, page 15.
The above conventional technique, however, does not consider the fact that a plurality of laser beams of different wavelengths have their focal positions biased in the direction normal to the recording layers due to the chromatic aberration of the focusing optical system, resulting in the inaccurate positioning of the laser beams to the respective recording layers.